OS reinstallation can restore instances to their initial statuses, which is a common way to recover the instance in the event of a system failure.
CVM supports the following two reinstallation types:
- Reinstall on the same platform: CVMs in all regions can be reinstalled to the OS of the same platform.
For example, you can always reinstall a Linux instance on a Linux OS, and Windows instance on a Windows OS.
- Reinstall on different platform: only CVMs in the Chinese mainland can be reinstalled to an OS of different platform.
For example, a Linux instance can be reinstalled on a Windows OS, and a Windows instance on a Linux OS.
- All newly added cloud disk and local disk instances support reinstallation on different platforms. Some existing 20 GB local disk instances do not support cross-platform reinstallation in the console. If you use such instances, you need to submit a ticket for application.
- Spot instances do not support system reinstallation.
- Preparation: After the re-installation, all data in the system disk are cleared. Please back up important data in advance. To retain your system runtime data, we recommend that you create a custom image and use this image to reinstall the system.
- Image selection: we recommend that you use the image provided by Tencent Cloud or your custom image instead of those from unknown or other sources. Do not perform other operations while the system disk is being reinstalled.
- Instance physical features: the public IP of the instance will not change.
- Specification limits: if you want to use an image with Windows 2016, or 2019 versions, the instance memory should be greater than 2 GB.
- Billing: if you adjust the size of the system disk (for cloud disks only), you will be charged according to the pricing standards of CBS. For more information, see Pricing List.
- Subsequent operations: after the system disk is reinstalled, the data in the data disks will not be affected and will be available for use only after the data disks are reattached.
You can use either of the following methods to reinstall the operating system:
- Log in to the CVM console.
- On the instance management page, proceed according to the actually used view mode:
- List view: in the row of the target instance, select More > Reinstall System as shown below:
- Tab view: on the page of the target instance, select More Actions > Reinstall the System in the top-right corner as shown below:
- In the pop-up window that appears, read notes and click Next.
- Select an image, set the instance login method, and click OK, as shown in the following figure:
Only when the image type is custom image or shared image can you select Follow image as the login method.
For more information, please see the ResetInstance API.
If the CVM has attached a data disk and you need to reinstall it on a different platform, please see the following documents about how to read data from the data disks of the original operating system: